Provider plugin for QCA (Qt crypto helper library).  Capabilities:

TLS, CMS, X.509, RSA, DSA, Diffie-Hellman, PKCS#7, PKCS#12, SHA1,
SHA224, SHA256, SHA384, SHA512, MD4, MD5, RIPEMD160, Blowfish, DES,
3DES, AES128, AES192, AES256, CAST5, HMAC (SHA1, MD5, RIPEMD160),
PBKDF1(SHA1), PBKDF2(SHA1).
